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<FONT color="green">001</FONT>    package gates;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    /**<a name="line.3"></a>
<FONT color="green">004</FONT>     *<a name="line.4"></a>
<FONT color="green">005</FONT>     * A representation of a toffoli gate made out of several other gates, the Hadamard, T, TDagger, S and CNot<a name="line.5"></a>
<FONT color="green">006</FONT>     * This representation can be found in &lt;a href="http://arxiv.org/abs/quant-ph/0301079"&gt;Grover's Algorithm: Quantum Database Search&lt;/a&gt; page 26<a name="line.6"></a>
<FONT color="green">007</FONT>     * @author Alex Bush<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     */<a name="line.9"></a>
<FONT color="green">010</FONT>    public class ToffoliComposite extends CompositeGate {<a name="line.10"></a>
<FONT color="green">011</FONT>    <a name="line.11"></a>
<FONT color="green">012</FONT>            /**<a name="line.12"></a>
<FONT color="green">013</FONT>             * Protected constructor to create an instance of this object<a name="line.13"></a>
<FONT color="green">014</FONT>             * <a name="line.14"></a>
<FONT color="green">015</FONT>             * @param control1 First control bit<a name="line.15"></a>
<FONT color="green">016</FONT>             * @param control2 Second control bit<a name="line.16"></a>
<FONT color="green">017</FONT>             * @param target Target bit<a name="line.17"></a>
<FONT color="green">018</FONT>             */<a name="line.18"></a>
<FONT color="green">019</FONT>            protected ToffoliComposite(int control1, int control2, int target) {<a name="line.19"></a>
<FONT color="green">020</FONT>                    super(createGates(control1,control2,target));<a name="line.20"></a>
<FONT color="green">021</FONT>            }<a name="line.21"></a>
<FONT color="green">022</FONT>            <a name="line.22"></a>
<FONT color="green">023</FONT>            /** Private method to create an array of gates needed to create a composition to send to superclass */<a name="line.23"></a>
<FONT color="green">024</FONT>            private static Gate[] createGates(int control1, int control2, int target){<a name="line.24"></a>
<FONT color="green">025</FONT>                    // Test arguments and throw appropriate exception<a name="line.25"></a>
<FONT color="green">026</FONT>                    if (control1 == control2 || control1 == target || control2 == target){<a name="line.26"></a>
<FONT color="green">027</FONT>                            throw new IllegalArgumentException("Control1, control2 and target must be unique");<a name="line.27"></a>
<FONT color="green">028</FONT>                    }<a name="line.28"></a>
<FONT color="green">029</FONT>                    Gate[] tg = new Gate[16];<a name="line.29"></a>
<FONT color="green">030</FONT>                    tg[0] = Factory.createHadamard(target);<a name="line.30"></a>
<FONT color="green">031</FONT>                    tg[1] = Factory.createCNot(control2, target);<a name="line.31"></a>
<FONT color="green">032</FONT>                    tg[2] = Factory.createTDagger(target);<a name="line.32"></a>
<FONT color="green">033</FONT>                    tg[3] = Factory.createCNot(control1, target);<a name="line.33"></a>
<FONT color="green">034</FONT>                    tg[4] = Factory.createT(target);<a name="line.34"></a>
<FONT color="green">035</FONT>                    tg[5] = Factory.createCNot(control2, target);<a name="line.35"></a>
<FONT color="green">036</FONT>                    tg[6] = Factory.createTDagger(target);<a name="line.36"></a>
<FONT color="green">037</FONT>                    tg[7] = Factory.createCNot(control1, target);<a name="line.37"></a>
<FONT color="green">038</FONT>                    tg[8] = Factory.createTDagger(control2);<a name="line.38"></a>
<FONT color="green">039</FONT>                    tg[9] = Factory.createT(target);<a name="line.39"></a>
<FONT color="green">040</FONT>                    tg[10] = Factory.createCNot(control1, control2);<a name="line.40"></a>
<FONT color="green">041</FONT>                    tg[11] = Factory.createHadamard(target);<a name="line.41"></a>
<FONT color="green">042</FONT>                    tg[12] = Factory.createTDagger(control2);<a name="line.42"></a>
<FONT color="green">043</FONT>                    tg[13] = Factory.createCNot(control1, control2);<a name="line.43"></a>
<FONT color="green">044</FONT>                    tg[14] = Factory.createT(control1);<a name="line.44"></a>
<FONT color="green">045</FONT>                    tg[15] = Factory.createS(control2);<a name="line.45"></a>
<FONT color="green">046</FONT>                    return tg;<a name="line.46"></a>
<FONT color="green">047</FONT>    <a name="line.47"></a>
<FONT color="green">048</FONT>            }<a name="line.48"></a>
<FONT color="green">049</FONT>    <a name="line.49"></a>
<FONT color="green">050</FONT>    }<a name="line.50"></a>




























































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